Unless the winter is very mild indeed, it will be too cold and wet to sow seeds outdoors this month. They’ll either rot or simply fail to germinate. Broad bean seeds sown under cloches or in cold frames are perhaps the only exception. Otherwise, it’s best to wait for a month or two. Indoors is a different matter, however. Germinating seeds, either in a propagator or in a heated greenhouse, will enable you to get a head start on the year.

Broad beans

If you didn’t sow broad beans outdoors at the end of last year, it may be possible now – as long as the ground is not frozen. Otherwise, sow them in pots and keep them under cover, or wait till spring when it’s warmer.

Sow broad beans in deep pots or in special root trainers to give the roots plenty of room to develop.

Garlic

Plant only if the weather is mild and only if the soil is not frozen or waterlogged. Otherwise, wait until February or March.

Winter salad leaves

It’s possible to harvest baby salad leaves all year round if you raise plants from seed under cover, in a brightly lit, well-ventilated spot such as a conservatory, greenhouse, or cold frame. For containers, use plastic mushroom or polystyrene fish boxes, or adapt wooden crates by lining them with plastic sheeting. Drill drainage holes, fill them with multi-purpose compost, and sow seeds generously. Try lettuces, rocket, spinach, kale, chard, Oriental leaves, and even a few herbs. You should have leaves large enough to harvest within about a month, and if you treat them as cut-and-come-again crops they should keep producing for three or four months.

Multi-sown onions

Sow seeds undercover in modules, with five seeds to each cell so the seedlings form a clump and can be planted out as a group.

Fruit trees and bushes

Plant new, bare-rooted trees and bushes during the winter months, when they are dormant. Prepare the ground in advance by clearing all weeds and digging in plenty of well-rotted manure or compost. If conditions are too cold or too wet, keep the plants in a sheltered, frost-protected spot such as a shed, and wait until next month.

Onions and leeks

To give onions and leeks the longest possible growing season, sow seeds in modules filled with fresh seed or potting compost and keep them indoors at a temperature of at least 10°C (50°F). Transplant them outdoors in March or April.

Onions sown indoors this month will need transplanting into small pots before hardening off and planting out in late March or April.

Peas

For a very early crop of peas – as early as May, if you are lucky – sow seeds in pots, modules, or guttering and keep them indoors until you can harden them off and plant them outdoors in March or April.

Radishes

Radishes germinate and grow quickly, and can give you an early spring crop if you sow seeds in pots or modules indoors, or under cover somewhere where the temperature at night won’t fall below about 5°C (40°F).

Rhubarb

Plant new sets or divide and re-plant old crowns at any time during the winter. Rhubarb will happily tolerate the cold but doesn’t like being waterlogged.